Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 720 [Rate centres in NPA 720] [Dial plan for NPA 720]

NXX: 228

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-228 A Denver CO DNVRCO37DS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656      

Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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